1 // SPDX-License-Identifier: GPL-2.0-only
2 /* linux/drivers/hwmon/s3c-hwmon.c
8  * S3C24XX/S3C64XX ADC hwmon support
21 #include <linux/hwmon-sysfs.h>
23 #include <linux/soc/samsung/s3c-adc.h>
24 #include <linux/platform_data/hwmon-s3c.h>
34  * struct s3c_hwmon - ADC hwmon client information
36  * @client: The client we registered with the S3C ADC core.
49  * s3c_hwmon_read_ch - read a value from a given adc channel.
54  * Read a value from the @channel with the proper locking and sleep until
55  * either the read completes or we timeout awaiting the ADC core to get
63 	ret = mutex_lock_interruptible(&hwmon->lock);  in s3c_hwmon_read_ch()
69 	ret = s3c_adc_read(hwmon->client, channel);  in s3c_hwmon_read_ch()
70 	mutex_unlock(&hwmon->lock);  in s3c_hwmon_read_ch()
77  * s3c_hwmon_show_raw - show a conversion from the raw channel number.
83  * ADC channel. This does a conversion and returns the raw (un-scaled)
89 	struct s3c_hwmon *adc = dev_get_drvdata(dev);  in s3c_hwmon_show_raw()  local
93 	ret = s3c_hwmon_read_ch(dev, adc, sa->index);  in s3c_hwmon_show_raw()
125 	return sysfs_create_group(&dev->kobj, &s3c_hwmon_attrgroup);  in s3c_hwmon_add_raw()
130 	sysfs_remove_group(&dev->kobj, &s3c_hwmon_attrgroup);  in s3c_hwmon_remove_raw()
141  * s3c_hwmon_ch_show - show value of a given channel
146  * Read a value from the ADC and scale it before returning it to the
160 	cfg = pdata->in[sen_attr->index];  in s3c_hwmon_ch_show()
162 	ret = s3c_hwmon_read_ch(dev, hwmon, sen_attr->index);  in s3c_hwmon_ch_show()
166 	ret *= cfg->mult;  in s3c_hwmon_ch_show()
167 	ret = DIV_ROUND_CLOSEST(ret, cfg->div);  in s3c_hwmon_ch_show()
173  * s3c_hwmon_label_show - show label name of the given channel.
188 	cfg = pdata->in[sen_attr->index];  in s3c_hwmon_label_show()
190 	return snprintf(buf, PAGE_SIZE, "%s\n", cfg->name);  in s3c_hwmon_label_show()
194  * s3c_hwmon_create_attr - create hwmon attribute for given channel.
197  * @channel: The ADC channel number to process.
215 	snprintf(attrs->in_name, sizeof(attrs->in_name), "in%d_input", channel);  in s3c_hwmon_create_attr()
217 	attr = &attrs->in;  in s3c_hwmon_create_attr()
218 	attr->index = channel;  in s3c_hwmon_create_attr()
219 	sysfs_attr_init(&attr->dev_attr.attr);  in s3c_hwmon_create_attr()
220 	attr->dev_attr.attr.name  = attrs->in_name;  in s3c_hwmon_create_attr()
221 	attr->dev_attr.attr.mode  = S_IRUGO;  in s3c_hwmon_create_attr()
222 	attr->dev_attr.show = s3c_hwmon_ch_show;  in s3c_hwmon_create_attr()
224 	ret =  device_create_file(dev, &attr->dev_attr);  in s3c_hwmon_create_attr()
231 	if (cfg->name) {  in s3c_hwmon_create_attr()
232 		snprintf(attrs->label_name, sizeof(attrs->label_name),  in s3c_hwmon_create_attr()
235 		attr = &attrs->label;  in s3c_hwmon_create_attr()
236 		attr->index = channel;  in s3c_hwmon_create_attr()
237 		sysfs_attr_init(&attr->dev_attr.attr);  in s3c_hwmon_create_attr()
238 		attr->dev_attr.attr.name  = attrs->label_name;  in s3c_hwmon_create_attr()
239 		attr->dev_attr.attr.mode  = S_IRUGO;  in s3c_hwmon_create_attr()
240 		attr->dev_attr.show = s3c_hwmon_label_show;  in s3c_hwmon_create_attr()
242 		ret = device_create_file(dev, &attr->dev_attr);  in s3c_hwmon_create_attr()
244 			device_remove_file(dev, &attrs->in.dev_attr);  in s3c_hwmon_create_attr()
255 	device_remove_file(dev, &attrs->in.dev_attr);  in s3c_hwmon_remove_attr()
256 	device_remove_file(dev, &attrs->label.dev_attr);  in s3c_hwmon_remove_attr()
260  * s3c_hwmon_probe - device probe entry.
265 	struct s3c_hwmon_pdata *pdata = dev_get_platdata(&dev->dev);  in s3c_hwmon_probe()
271 		dev_err(&dev->dev, "no platform data supplied\n");  in s3c_hwmon_probe()
272 		return -EINVAL;  in s3c_hwmon_probe()
275 	hwmon = devm_kzalloc(&dev->dev, sizeof(struct s3c_hwmon), GFP_KERNEL);  in s3c_hwmon_probe()
277 		return -ENOMEM;  in s3c_hwmon_probe()
281 	mutex_init(&hwmon->lock);  in s3c_hwmon_probe()
283 	/* Register with the core ADC driver. */  in s3c_hwmon_probe()
285 	hwmon->client = s3c_adc_register(dev, NULL, NULL, 0);  in s3c_hwmon_probe()
286 	if (IS_ERR(hwmon->client)) {  in s3c_hwmon_probe()
287 		dev_err(&dev->dev, "cannot register adc\n");  in s3c_hwmon_probe()
288 		return PTR_ERR(hwmon->client);  in s3c_hwmon_probe()
291 	/* add attributes for our adc devices. */  in s3c_hwmon_probe()
293 	ret = s3c_hwmon_add_raw(&dev->dev);  in s3c_hwmon_probe()
299 	hwmon->hwmon_dev = hwmon_device_register(&dev->dev);  in s3c_hwmon_probe()
300 	if (IS_ERR(hwmon->hwmon_dev)) {  in s3c_hwmon_probe()
301 		dev_err(&dev->dev, "error registering with hwmon\n");  in s3c_hwmon_probe()
302 		ret = PTR_ERR(hwmon->hwmon_dev);  in s3c_hwmon_probe()
306 	for (i = 0; i < ARRAY_SIZE(pdata->in); i++) {  in s3c_hwmon_probe()
307 		struct s3c_hwmon_chcfg *cfg = pdata->in[i];  in s3c_hwmon_probe()
312 		if (cfg->mult >= 0x10000)  in s3c_hwmon_probe()
313 			dev_warn(&dev->dev,  in s3c_hwmon_probe()
317 		if (cfg->div == 0) {  in s3c_hwmon_probe()
318 			dev_err(&dev->dev, "channel %d divider zero\n", i);  in s3c_hwmon_probe()
322 		ret = s3c_hwmon_create_attr(&dev->dev, pdata->in[i],  in s3c_hwmon_probe()
323 					    &hwmon->attrs[i], i);  in s3c_hwmon_probe()
325 			dev_err(&dev->dev,  in s3c_hwmon_probe()
328 			for (i--; i >= 0; i--)  in s3c_hwmon_probe()
329 				s3c_hwmon_remove_attr(&dev->dev,  in s3c_hwmon_probe()
330 							      &hwmon->attrs[i]);  in s3c_hwmon_probe()
339 	hwmon_device_unregister(hwmon->hwmon_dev);  in s3c_hwmon_probe()
342 	s3c_hwmon_remove_raw(&dev->dev);  in s3c_hwmon_probe()
345 	s3c_adc_release(hwmon->client);  in s3c_hwmon_probe()
355 	s3c_hwmon_remove_raw(&dev->dev);  in s3c_hwmon_remove()
357 	for (i = 0; i < ARRAY_SIZE(hwmon->attrs); i++)  in s3c_hwmon_remove()
358 		s3c_hwmon_remove_attr(&dev->dev, &hwmon->attrs[i]);  in s3c_hwmon_remove()
360 	hwmon_device_unregister(hwmon->hwmon_dev);  in s3c_hwmon_remove()
361 	s3c_adc_release(hwmon->client);  in s3c_hwmon_remove()
368 		.name		= "s3c-hwmon",
377 MODULE_DESCRIPTION("S3C ADC HWMon driver");
379 MODULE_ALIAS("platform:s3c-hwmon");